Smith-Gobat wants to scale a daunting buttress called The Nose on the 2307m El Capitan rock formation more quickly than anyone has before.

"In rock climbing, women are close to men, if you look solely at pure difficulty, but rarely do they compete on the same level as the guys," said the Christchurch-based climber, whose latest expedition is partly funded with $10,000 from Sport New Zealand Hillary Expeditions.

"I want to show that we women are just as capable, on any terrain."

In free climbing, rope is used only to prevent falling and not to ascend. Free-climb ascents are rarely attempted by a lone woman.

Smith-Gobat, a former semiprofessional skier who has become one of the world's best female pro rock climbers, already holds the female speed record for scaling The Nose.

Her first challenge at Yosemite this month - depending on the weather, her preparation and energy levels - is to become the fourth person to free-climb it.

She will then attempt to become the first woman to free-climb a link-up of El Capitan and the Half Dome formation (1444m) in under 24 hours.

Her third challenge, she says, is her toughest: breaking The Nose speed-climbing record for men or women of two hours and 26 minutes.

"I have several objectives in Yosemite this year, all of which will be very tough but in different ways," she said from Yosemite National Park.

"The speed record on The Nose is my first objective. This is not very difficult in terms of the individual moves I'll be doing, but it will be very difficult to do everything efficiently enough to break the current record.

"The free link-up of Free Rider [on El Capitan] and Half Dome will be very tough because of the sheer amount of relatively difficult climbing I intend to do over a 24-hour period."

She holds several female "first climbs" of difficult faces in New Zealand, the US and France.

Her attempts have attracted the close attention of the highly competitive rock-climbing world.

Smith-Gobat, who spends much of each year travelling in search of new climbs, says she climbs in part to inspire other female climbers.